We have been interested in determining the minimally required elements in the sperm head that are necessary in order for the paternal genome to participate in embryogenesis. We used an ionic detergent, mixed alkyltrimethylammonium bromide (ATAB), plus dithiothreitol (DTT) to remove the acrosome and almost all of the perinuclear theca, leaving only the sperm nucleus morphologically intact. We al...

There is a fundamental body of evidence suggesting that activated apoptosis signaling in ejaculated human sperm negatively influences their fertilization potential. However, it is still controversial whether this apoptotic signaling is a relic of an abortive apoptosis related to spermatogenesis or if it should be regarded as a functional preformed pathway in mature sperm leading to stereotypica...

BACKGROUND The cytoplasm of eukaryotic cells is a highly dynamic compartment where membranes readily undergo fission and fusion to reorganize the cytoplasmic architecture, and to import, export and transport various cargos within the cell. The double membrane of the nuclear envelope that surrounds the nucleus, segregates the chromosomes from cytoplasm and regulates nucleocytoplasmic transport t...

Post-copulatory sexual selection in the form of sperm competition is known to influence the evolution of male reproductive proteins in mammals. The relationship between sperm competition and regulatory evolution, however, remains to be explored. Protamines and transition nuclear proteins are involved in the condensation of sperm chromatin and are expected to affect the shape of the sperm head. ...

We explored the relationship between sperm chromatin integrity, hormone levels, seminal plasma total antioxidant capacity (TAC), and routine sperm parameters in men with male factor (MF, n = 81) and non-male factor (NMF, n = 52) infertility. Semen and blood were collected and examined from men undergoing evaluation for infertility in the Avicenna Infertility Clinic. We have examined each patien...

We report the isolation and characterization of a new nuclear structure from spermatozoa of the golden Syrian hamster which we term the nuclear annulus. The nuclear annul us was located at the implantation fossa, the point at which the tail is joined to the sperm head, inside the nucleus adjacent to the inner nuclear envelope. Extraction of sperm nuclei with 2 M NaC1 and 10 mM dithiothreitol ca...

Background: Diabetes mellitus as a chronic disease can cause fertility problems in male human population. In fact, it exerts sever damages in testicular tissue and subsequently reduces total number of normal sperms and semen volume. Therefore, this study is designed to evaluate the protective effect of Equisetum arvense extract on sperm quality, DNA damage and maturation in diabetic male mice. ...

Sperm nuclear migration during fertilization in Arabidopsis and rice has recently been found to be actin-dependent, but the driving force behind this actin cytoskeleton-dependent motion is unclear. Here, we confirmed that the actin-dependent sperm nuclei migration during fertilization is a conserved mechanism in plants. Using in vitro fertilization systems, we showed that a functional actin is ...

OBJECTIVES To determine the differences among the creatine kinase (CK) levels in the spermatozoa of subfertile men with mild, moderate, or severe oligospermia and to examine the differences in CK activity between infertile patients with various clinical diagnoses and a group of normal healthy donors (control). CK is a marker of sperm maturity that correlates with the sperm fertilizing capacity....

BACKGROUND There are still concerns about the safety of intracytoplasmic sperm injection (ICSI) due to its brief clinical record and lack of animal testing. Testicular and epididymal sperm are now used routinely for ICSI in patients with obstructive azoospermia. The use of such immature sperm compounds fears, since little is known of their mitochondrial and nuclear DNA quality. METHODS A modi...